Anatomical Study of Pelvic Nerves in Relation to Seminal Vesicles, Prostate and Urethral Sphincter: Immunohistochemical Staining, Computerized Planimetry and 3-Dimensional Reconstruction

Radical Prostatectomy and Anatomical Controversies: The Urethral Sphincter and the Elusive Continence Mechanisms

Prostate cancer incidence is rising [...].

Modified completely intrafascial radical cysprostatectomy for bladder cancer: a single-center, blinded, controlled study

BACKGROUND

We have proposed a modified, completely intrafascial radical cysprostatectomy (RC) to treat bladder cancer patients with the aim of preserving the patients' post-surgical urinary control and erectile function. This study aimed to evaluate the oncological and functional outcomes of this innovation relatively to that with the conventional technique.

METHODS

A retrospective, single-center, blinded, and controlled study was conducted using the medical data of patients since the past 5 years from the hospital database. A total of 44 patients were included, including 20 who received complete intrafascial cysprostatectomy and 24 who received conventional interfascial surgeries. The patients' continent and sexual information of 1-year follow-up after the surgery were extracted. The oncological and functional outcomes of the 2 groups were compared and analyzed.

RESULTS

The demographics parameters of the 2 groups showed no significant difference. The results of follow-up of the oncological outcomes did not reveal any significant difference between the completely intrafascial group and the conventional interfascial group in terms of the positive surgical margins, local recurrences, and distant metastasis. Patients following neobladder diversion in the intrafascial group showed a faster recovery of the urinary control, with a 76.9% (10/13) daytime continent rate at 3-month, as well as 46.2% (6/13) and 58.3% (7/12) nighttime continent rates at 3-month and 6-month, respectively. Regarding the sexual functions, our results revealed significant advantages in favor of completely intrafascial technique on the post-surgical International Index of Erectile Function (IIEF)-5 score at 3-, 9-, and 12-month follow-up relative to that with the conventional interfascial process. Thus, the IIEF score of patients in the intrafascial group was 11.4 ± 3.5 at 3-month, 14.1 ± 3.6 at 9-month, and 15.2 ± 3.8 at 12-month follow-up after the cystectomy, which was significantly greater than that of the patients in the control group.

CONCLUSIONS

Our novel data illustrated that the modified completely intrafascial technique could result in a better sexual function and faster continence recovery for patients following RC, without any compromise in the cancer control. Thus, this technique could be considered as an alternative extirpative technique for bladder cancer treatment in a clinical setting.

The male external urethral sphincter is autonomically innervated

INTRODUCTION

The aim of the present study was to describe autonomic urethral sphincter (US) innervation using specific muscular and neuronal antibody markers and 3D reconstruction.

MATERIAL AND METHODS

We performed en-bloc removal of the entire pelvis of three male human fetuses between 18 and 40 weeks. Serial whole mount sections (5 μm intervals) were stained and investigated. The sections were stained with Masson's trichrome and Eosin Hematoxylin, and immunostained with: anti-SMA antibody for smooth muscle; anti-S100 antibody for all nerves; and anti-PMP22 antibody, anti-TH antibody, anti-CGRP antibody, anti-NOS antibody for somatic, adrenergic, sensory and nitrergic nerve fibers, respectively. The slides were digitized for 3D reconstruction to improve topographical understanding. An animated reconstruction of the autonomic innervation of the US was generated.

RESULTS

The external and internal US are innervated by autonomic nerves of the inferior hypogastric plexus (IHP). These nerves are sympathetic (positive anti-TH antibody), sensory (positive anti-CGRP antibody), and nitrergic (positive anti-NOS antibody). Some autonomic fibers run within the neurovascular bundles, posterolaterally. Others run from the IHP to the posteromedial aspect of the prostate apex, above an through the rectourethral muscle. The external US is also innervated by somatic nerves (positive anti-PMP22 antibody) arising from the pudendal nerve, joining the midline but remaining below the rectourethral.

CONCLUSIONS

This study provides anatomical evidence of an autonomic component in the innervation of the external US that travels in the neurovascular bundle. During radical prostatectomy, the rectourethral muscle and the neurovascular bundles are to be preserved, particularly during apical dissection.

Complications of transrectal prostate biopsy in our context. International multicenter study of 3350 patients

INTRODUCTION

Prostate cancer is the most common visceral neoplasm in men and the second one in the United States with the highest mortality behind lung cancer and ahead of colorectal cancer. While prostate cancer mortality rates have been reduced in the United States, Austria, United Kingdom and France, 5-year survival rates have been incremented in Sweden, probably due to a higher diagnostic activity and non-lethal tumor detection. TRPB usually has low rates of serious complications, with a not negligible number of minor complications. Mortality directly associated with this procedure is low and usually related to septic shock. The main complications derived from prostate biopsy can be infectious (mild or severe) and non-infectious (hematuria consistent with hemorrhage, urethral bleeding, rectal bleeding or hemospermia, acute urinary retention, pain or vasovagal reactions).

MATERIAL AND METHOD

The objective of the study is to compare three usual TRPB protocols and their relationship with the incidence of complications. Retrospective multicenter observational study conducted in three countries (Spain, Italy and Portugal). We have reviewed the medical records of 3350 men who underwent TRPB to evaluate the existence of prostate cancer, with a minimum evolutionary control of 6months.

RESULTS

The mean age was 65,50years, median 66, range 43-79. The subgroup analysis showed that younger patients had higher rates of acute urine retention (AUR) (P=.0000001). Likewise, our results revealed that younger patients presented more procedural pain (P=.0000001) than older patients. Regarding PSA, the mean value was 10.44, SD 7.73, median 8.15, range 0.98-68.09. A higher body mass index (BMI) was not associated with further infection (P=.000004). When performing the multivariate analysis, it was found that the significant variables in the general group were: age (P=.0013), PSA (P=.0402), local infiltration anesthesia (P=.0001) and prophylaxis with metronidazole +tobramycin +amoxicillin/clavulanic acid +gentamicin (P=.0001), presenting a normal distribution with high confidence interval (95%) and significant correlation. Prophylaxis is the most significant variable for no complications and pain (P=.0001), age (P=.0013) and prophylaxis (P=.0001) are for bleeding, age (P=.0013), prophylaxis and PSA (P=.0001) are for infection, and finally, age (P=.0013), anesthesia with local infiltration and prophylaxis (P=.0001) and PSA (P=.0402) are for AUR.

CONCLUSIONS

Sedation has fewer side effects and complications related to the transrectal prostate biopsy procedure with respect to transrectal local anesthesia. The choice of the antibiotic prophylaxis scheme is decisive in the onset of complications arising from the performance of a transrectal prostate biopsy.

Site-dependent differences in the composite fibers of male pelvic plexus branches: an immunohistochemical analysis of donated elderly cadavers

Background

Although the pelvic autonomic plexus branches are considered to be a mixture of sympathetic and parasympathetic nerves, little is known regarding the composite fibers of the pelvic plexus branches. This study aimed to investigate the immunohistochemical features of sympathetic and parasympathetic nerves in the pelvic autonomic plexus branches.

Methods

Using 10 donated elderly male cadavers, the detailed topohistology of nerve fibers at and around the bladder, seminal vesicle, prostate, and rectum was examined. Neuronal nitric oxide synthase (nNOS) and vasoactive intestinal polypeptide (VIP) were used as parasympathetic nerve markers; tyrosine hydroxylase (TH) was used as a sympathetic nerve marker. The myenteric plexus of the colon was utilized as a positive control.

Results

Most nerve fibers in the bladder, seminal vesicle, prostate, and rectum were both nNOS- and TH-positive. Thus, pelvic plexus branches were classified into two types: 1) triple-positive mixed nerves (nNOS+, VIP+, TH+, thick myelinated fibers + or -) and 2) double-positive mixed nerves (nNOS+, VIP-, TH+, thick myelinated fibers + or -). Notably, triple-positive nerves were localized within the posterosuperior part of the plexus (near the rectum) and travelled anteroinferiorly toward the posterolateral corner of the prostate. The posteriorly and inferiorly located nerves were predominantly composed of parasympathetic, rather than sympathetic, fibers. In contrast, nerve fibers within and along the bladder and seminal vesicle contained either no or few VIP-positive nerves. These superiorly located nerves were characterized by clear sympathetic nerve dominance.

Conclusions

The nerves of the pelvic plexus branches were clearly classified into nerves around the bladder and seminal vesicle (VIP-negative) and nerves around the prostate (VIP-positive). Although nNOS- and VIP-positive nerve fibers are candidate cavernous nerves, cavernous nerve identity cannot be definitively concluded for these nerves in the periprostatic region.

Peri-prostatovesicular smooth muscle tumors of undetermined malignant potential: a case report

INTRODUCTION

Smooth muscle tumors of undetermined malignant potential (STUMPs) are atypical smooth muscle tumors, most of which derived from uterine tissue. STUMPs of male genitourinary system and of the male pelvic organs are uncommon.

CASE DESCRIPTION

In this report, we describe the first case of peri-prostatovesicular STUMP that was treated with laparoscopic excision, in a young asymptomatic man.

CONCLUSIONS

In most cases, the definitive diagnosis can be made only after surgical resection and accurate histological examination. The usefulness of adjuvant chemotherapy remains unclear, and a standardized follow-up protocol has not been described.

A Critical Analysis of the Current Knowledge of Surgical Anatomy of the Prostate Related to Optimisation of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy: An Update

CONTEXT

In 2010, we published a review summarising the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control and the functional outcome of prostatectomy.

OBJECTIVE

To provide an update based on new literature to help the surgeon improve oncologic and surgical outcomes of radical prostatectomy (RP).

EVIDENCE ACQUISITION

We searched the PubMed database using the keywords radical prostatectomy, anatomy, neurovascular bundle, nerve, fascia, pelvis, sphincter, urethra, urinary continence, and erectile function. Relevant articles and textbook chapters published since the last review were critically reviewed, analysed, and summarised. Moreover, we integrated aspects that were not addressed in the last review into this update.

EVIDENCE SYNTHESIS

We found new evidence for several topics. Up to 40% of the cross-sectional surface area of the urethral sphincter tissue is laterally overlapped by the dorsal vascular complex and might be injured during en bloc ligation. Denonvilliers fascia is fused with the base of the prostate in a horizontal fashion dorsally/caudally of the seminal vesicles, requiring sharp detachment when preserved. During extended pelvic lymph node dissection, the erectile nerves are at risk in the presacral and internal iliac area. Dissection planes for nerve sparing can be graded according to the amount of tissue left on the prostate as a safety margin against positive surgical margins. Vascular structures can serve as landmarks. The urethral sphincter and its length after RP are influenced by the shape of the apex. Taking this shape into account allows preservation of additional sphincter length with improved postoperative continence.

CONCLUSIONS

This update provides additional, detailed information about the surgical anatomy of the prostate and adjacent tissues involved in RP. This anatomy remains complex and widely variable. These details facilitate surgical orientation and dissection during RP and ideally should translate into improved outcomes.

PATIENT SUMMARY

Based on recent anatomic findings regarding the prostate and its surrounding tissue, the urologist can individualise the dissection during RP according to cancer and patient characteristics to improve oncologic and functional results at the same time.